With rental and equipment fee, $50 000 may be totally enough to build a business up from scratch unless there is a great business idea.
I can only think of powering up using $50 000 about 23 K steem power to develop our business in steemit since we are believers of this platform.

1. Use the 23 K steem power and create an extra minnow assistance bot. In this way, no rental fee and equipment needed and can take our time to build
2. Allow more short term rental at a low fee to kick start a minnow for a short term to build enough SP to survive
3. Everything that minnowbooster and some of the steemit programmes like steembasicincome, qurator etc can be explored to see how we can build a simple low profit business to help others here